Each positive step you take can raise your score ten to twenty points over a three-month period. Major steps, such as substantially lowering your debt, will result in a higher increase.
If you are thinking that you would like to buy a house in a year or even longer, now is the time to start working on your credit history. Since you must allow yourself at least three months to change your score, longer to raise your score an appreciable amount, do not wait until you are ready to buy to start trying to raise your score.
The idea behind improving your credit score is to make you look more financially responsible so you qualify for a better loan.